Narrated Ibn 'Abbas:"A Bedouin came to the Messenger of Allah (ﷺ) and said: 'How shall I know that you are a Prophet?' He said: 'If I were to call this date cluster from this palm tree, would you bear witness that I am the Messenger of Allah?' So the Messenger of Allah (ﷺ) called it and they started to fall from the tree, until they fell towards the Prophet (ﷺ), then he said: 'Go back,' and it went back. So the Bedouin accepted Islam

English translation · Jami' at-Tirmidhi